﻿// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

#nullable disable

using Microsoft.ApplicationInsights.Channel;
using Microsoft.ApplicationInsights.Extensibility.Implementation;
using IChannelTelemetry = Microsoft.ApplicationInsights.Channel.ITelemetry;

namespace Microsoft.DotNet.Cli.Telemetry.PersistenceChannel;

/// <summary>
///     This class handles all the logic for flushing the In Memory buffer to the persistent storage.
/// </summary>
internal class FlushManager
{
    /// <summary>
    ///     The storage that is used to persist all the transmissions.
    /// </summary>
    private readonly BaseStorageService _storage;

    /// <summary>
    ///     Initializes a new instance of the <see cref="FlushManager" /> class.
    /// </summary>
    /// <param name="storage">The storage that persists the telemetries.</param>
    internal FlushManager(BaseStorageService storage)
    {
        _storage = storage;
    }

    /// <summary>
    ///     Gets or sets the service endpoint.
    /// </summary>
    /// <remarks>
    ///     Q: Why flushManager knows about the endpoint?
    ///     A: Storage stores Transmission objects and Transmission objects contain the endpoint address.
    /// </remarks>
    internal Uri EndpointAddress { get; set; }

    /// <summary>
    ///     Persist the in-memory telemetry items.
    /// </summary>
    internal void Flush(IChannelTelemetry telemetryItem)
    {
        if (telemetryItem != null)
        {
            byte[] data = JsonSerializer.Serialize([telemetryItem]);
            Transmission transmission = new(
                EndpointAddress,
                data,
                "application/x-json-stream",
                JsonSerializer.CompressionType);

            _storage.EnqueueAsync(transmission).ConfigureAwait(false).GetAwaiter().GetResult();
        }
    }
}
